Pesach, ("Passover") is the major spring festival and commemorates the Biblical Exodus from Egypt. The ritual observance of this holiday centers around a special home service called the Seder (meaning "order") and a festive meal; the prohibition of chametz (leaven); and the eating of matzo (an unleavened bread). Click here to read more about Passover.
From the Clergy's Study:
"Thoughts for Your Seders" by Rabbi Michelle Missaghieh